1- upper GI Flashcards
what components of GI tract are in head?
oral cavity then pharynx
what components of GI tract are in neck?
pharynx then oesophagus
what components of GI tract are in chest?
oesophagus
what components of GI tract are in abdomen?
stomach, small intestine, most of large intestine and most of accessory organs of GI
what components of GI tract are in pelvis?
rectum and then anal canal
what joint opens your mouth?
temporomandibular joint (TMJ)
what 3 pairs of muscles close your jaw?
- masseter (from angle of mandible up to zygomatic bone -lateral aspect)
- temporalis muscle (from temporal fossa down to coronoid process of mandible)
- medial pterygoid (mirror image of masseter but on medial rather than lateral - runs medial of mandible )
what pair of muscles opens jaw?
lateral pterygoid (from condoid to pterygoid plates) - actually pulls mandible forwards which allows mandible to swing open
what nerves control the muscles that open + close the jaw?
mandibular division of trigeminal nerve - CN V3
what type of joint is temporomandibular joint?
modified hinge synovial joint
what is purpose of condylar process?
it’s on mandible and it’s purpose is to try and prevent jaw moving too far forward
what is the course of cranial nerve V3?
arises from pons, passes through foramen ovale and to muscles of mastication + sensory area (in lower part of face + skull)
what nerve fibers are carried in cranial nerve V3?
sensory + motor
what is oral vestibule?
like hallway into oral cavity
what is the oral cavity?
in between upper + lower dental arch. when mouth at rest - it’s pretty much fully taken up by tongue
what are palatine tonsils?
collection of lymph nodes trying to detect when things get into system
→tonsils sit in between 2 arches
what is the uvula?
dangly bit in middle of mouth
how many teeth are there if normal set of completely erupted?
32 teeth
what are the teeth in your mouth?
you have upper + lower dental arch (right and left of both)
- there are 8 teeth per area e.g. in right upper dental arch
1+2 = incisors
3 = canine
4+5 = premolars
6,7,8 = molars
(8 = wisdom tooth)
what are the 3 major paired salivary glands?
- parotid (at ear)
- submandibular (under mandible and wraps around back) - also called whartons duct
- sublingual (underneath tongue)
how many salivary glands do you have?
loads - but i just need to know 3 major pairs (parotid, submandibular, sublingual)
what is the largest salivary gland? and what is it’s route for secretion?
parotid gland - secretes through duct that pierces through cheek muscle (buccinator muscle)
before putting anything in patients mouth for endoscope what is important to ask?
if any loose teeth or recent dental work to prevent aspiration
what nerve supplies the superior half of mouth + oral cavity?
CN V2 = maxillary division of trigeminal nerve
what nerve supplies the inferior half of the mouth?
CN V3 = mandibular division of trigeminal nerve
what is the
a) superior half
b) inferior half
of mouth?
a) gingiva (gums) of oral cavity + palate
b) gingiva (gums) of oral cavity and floor of mouth
what part of the mouth is most sensitive to touch?
posterior wall of oropharynx is extremely sensitive to touch
what nerve supplies the posterior wall of oropharynx?
CN IX (glossopharyngeal)
what is the purpose of gag reflex - what nerves are involved?
it’s there as a protective reflex
CN IX = carries sensory part
CN IX + CN X = carry motor part
- they work together to constrict the pharynx in attempt to close off
what is course/route of CN V2? and what nerve fibers does it carry?
maxillary division of trigeminal nerve
coming form pons but goes through foramen rotundum and only carries sensory innervation - supplied mid part of face
what nerve fibers does CN IX carry?
special sensory, sensory, motor, visceral afferent + parasympathetic
what is course of CN IX?
From medulla then through jugular foramen to posterior wall of oropharynx (sensory), parotid gland (secretomotor) and post. 1/3rd Tongue (Sensation and Taste)
what are the divisions of the tongue?
think like from side view
- anterior (2/3), it’s like top 2/3
- posterior (1/3), like bottom 1/3
where is
a) anterior of tongue
b) posterior of tongue
a) classed as in oral cavity (think like top 2/3 of tongue)
b) not classed as oral cavity, in oral pharynx (think like bottom 1/3 of tongue)
what nerves supply anterior of tongue?
general sensation = supplied by CN V3
special sensation(taste) = supplied by VII (facial nerve)
what nerves supply posterior tongue?
general + special sensory supplied by CN IX
what nerve fibers do CN VII carry?
special sensory, sensory, motor, parasympathetic
what is route of CN VII?
in internal acoustic meatus (bony canal located within intemporal bone,is a passageway for many important structures related to hearing and balance). CN VII then comes out the stylomastoid foramen, it then splits in 2:
- passes through atiomo mastoid foramen, just to stimulate muscles for moving your face
- little branch = the chorda tympani branch (passes over tympani, eardrum) of CN VII hitches a ride with lingual branch of CN V3 so contains taste and parasympathetic axons for salivary glands
what does CN VII supply?
-the muscles of facial expression
- the chorda tympani branch (which comes off CN VII and joins CN V3) supplies the sublingual salivary gland and submandibular salivary gland
what nerves supply tongue muscles?
all supplied by CN XII (hypoglossal) except palatoglossus as part of palate so supplied by CN XI
what are the 4 pairs of extrinsic tongue muscles?
- palatoglossus (from palate)
- styloglossus (from styloid process)
- hyoglossus (hyoid bone)
- genioglossus (genial tubercles)
what is example of intrinsic tongue muscle?
Superior longitudinal muscle,Inferior longitudinal muscle, Transverse muscle
what is an extrinsic tongue muscle?
start externally and then insert onto tongue- these ones move position of tongue
what is an intrinsic tongue muscle?
purely found in tongue - all attachments in tongue - these ones change shape of tongue
what is course of CN XII?
from medulla then through hypoglossal canal to extrinsic + intrinsic muscle of tongue (except palatoglossus)
what nerve fibers are in CN XII?
only motor
where is upper oesophageal sphincter?
cricopharyngeus = C6
once past this muscle your in oesophagus
what is midline raphe?
where 2 sides of the pharyngeal wall are joined together posteriorly
what are muscles on posterior neck?
- inner layer of longitudinal muscles
- superior, middle and inferior circular/constrictor muscles = they overlap each other like cups and contract from superior, medially and then inferior
what nerves supply constrictor muscles on posterior of neck?
CN X
what happens when contraction of posterior muscles of pharynx?
- Contraction of these muscles shortens the pharynx and narrows its diameter, assisting in the peristaltic movement of the bolus of food or liquid downward toward the esophagus.
- Additionally, the superior pharyngeal constrictor muscle also contributes to closing the nasopharynx, preventing food or liquid from entering the nasal cavity.
how do you insert endoscope? i.e you have to get patient to swallow, what is this process?
- tongue pushes bolus of food towards oropharynx (voluntary)
- soft palate elevated + larynx elevated closing laryngeal inlet (involuntary)
- circular layer of pharyngeal constrictor muscles contract (involuntary)
- bolus of food enters oesophagus and travels inferiorly by peristalsis (involuntary)
what normal constriction can occur in oesophagus causing problems swallowing?
a) cervical constriction?
b) thoracic constriction?
c) diaphragmatic constricion
a) contraction of cricopharyngeus muscle (upper oesophageal sphincter)
b) arch of aorta + left main bronchus
c) result of passing through diaphragm (lower oesophageal sphincter)
what level does oesophagus start?
vertebral level C6 - at inferior edge of cricopharyngeus muscle
what is the upper and lower oesophageal sphincter?
upper oesophageal sphincter is actual anatomical sphincter = cricopharyngeus muscle
lower oesophageal sphincter is just physiological (when passing through diaphragm)
where and what is oesophageal plexus?
= contains parasympathetic nerves (vagal trunks) and sympathetic nerves which influence enteric nervous system to speed or slow peristalsis
- they run on surface of oesophagus to supply smooth muscle within walls (distally)
what nerve fibre influences enteric nervous system to speed up peristalsis?
parasympathetic
what nerve fibre influences enteric nervous system to slow down peristalsis?
sympathetic
where does oesophagus run?
starts in root of neck and runs posterior to trachea and anterior to vertebral bodies - then in chest runs posterior to heart - then in abdomen goes through diaphragm and immediately connects with stomach
what are the factors that make lower oesophageal sphincter effect?
- Contraction of diaphragm
- Intra-abdominal pressure slightly higher than intragastric pressure so helps close off oesophagus at bottom
- Oblique angle at which oesophagus enters the cardia of stomach(prevents reflux back into oesophagus)
what is z-line?
very clear change in mucosa = just superior to gastro-oesophageal junction
where does stomach lie?
- across 3 regions of abdomen
- Lies mainly in the left hypochodrium, epigastric and umbilical regions when the patient is supine
- Is said to be ‘J’ shaped
what are the different structures of stomach?
(cardia, fundus, body, rugae, incisura angularis, pyloric sphincter)
cardia = the tube where oesophagus goes into stomach
fundus = superior part
body = main area
rugae = series of ridges produced by folding of wall of organ
incisura angularis = angular notch in lesser curve of stomach
pyloric sphincter (pylorus) = 1st part of duodenum
pyloric antrum = region between the sharp indentation at the lower third of the stomach (incisura angularis) and the junction of the pylorus with the duodenum
